This is an Alton Brown recipe. It's super easy and uses only one dish (it's all made in an electric skillet).
It starts by sweating the onions for about 45 minutes in a whole bunch of butter. Can't go wrong there.
But then during the soup making part he has you add 10 ounces of apple cider. At first I thought I liked it okay..defintiely a little different from the usual onion soup. Then as I delved deeper, I decided it was definitely too sweet. So next time, I will decrease the apple cider and add more broth. I think with those changes it will be incredible.
Who am I to question Alton Brown? Well, no one really. Don't tell him, okay?